∞ generated and posted on 2016.08.24 ∞
Amino acid-based polymeric substance which, as normally configured, completely spans a lipid bilayer.
Membrane transport proteins are transmembrane proteins. This makes sense mechanistically since what these proteins do is to connect one side of a membrane to the other. Not all transmembrane proteins, by contrast, are transport proteins.
Most cells possess substantial suites of transmembrane proteins, at least one for every polar/relatively large component that they need to transport into their cells, or transport out.